CVE-2021-42835

An issue was discovered in Plex Media Server through 1.24.4.5081-e362dc1ee. An attacker (with a foothold in a endpoint via a low-privileged user account) can access the exposed RPC service of the update service component. This RPC functionality allows the attacker to interact with the RPC functionality and execute code from a path of his choice (local, or remote via SMB) because of a TOCTOU race condition. This code execution is in the context of the Plex update service (which runs as SYSTEM).

CVSS v3.0 7.0 HIGH
CVSS v2.0 6.9 MEDIUM

7.0^/10

CVSS v3.0 : HIGH

Vector :

Exploitability : 1.0 / Impact : 5.9

Attack Vector LOCAL

Attack Complexity HIGH

Privileges Required LOW

User Interaction NONE

Confidentiality Impact HIGH

Integrity Impact HIGH

Availability Impact HIGH

Scope UNCHANGED

6.9^/10

CVSS v2.0 : MEDIUM

Vector : AV:L/AC:M/Au:N/C:C/I:C/A:C

Exploitability : 3.4 / Impact : 10.0

Access Vector LOCAL

Access Complexity MEDIUM

Authentication NONE

Confidentiality Impact COMPLETE

Integrity Impact COMPLETE

Availability Impact COMPLETE

References

Link	Resource
https://forums.plex.tv/t/security-regarding-cve-2021-42835/761510	Vendor Advisory
https://bugsec.com/experts_teams/	Third Party Advisory
https://ir-on.io/2021/12/02/local-privilege-plexcalation/	Exploit Third Party Advisory
https://www.plex.tv/media-server-downloads/	Product Vendor Advisory

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Configurations

Configuration 1 (hide)

AND

cpe:2.3:a:plex:media_server:*:*:*:*:*:*:*:*

cpe:2.3:o:microsoft:windows:-:*:*:*:*:*:*:*

Information

Published : 2021-12-08 07:15

Updated : 2021-12-13 09:14

NVD link : CVE-2021-42835

Mitre link : CVE-2021-42835

JSON object : View

CWE

CWE-367

Time-of-check Time-of-use (TOCTOU) Race Condition

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Products Affected

microsoft

windows

plex

media_server

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